Skip to content

Q
qemu

openeuler / qemu

通知 10
Star 0
Fork 0
Q
qemu

体验新版 GitCode，发现更多精彩内容 >>

切换分支/标签
  1. 03 7月, 2020 2 次提交
    • D
      virtio-pci: Proxy for virtio-mem · 0b9a2443
      由 David Hildenbrand 提交于 
      Let's add a proxy for virtio-mem, make it a memory device, and
pass-through the properties.
Reviewed-by: NPankaj Gupta <pankaj.gupta.linux@gmail.com>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcel Apfelbaum <marcel.apfelbaum@gmail.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-12-david@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      0b9a2443
    • D
      virtio-mem: Paravirtualized memory hot(un)plug · 910b2576
      由 David Hildenbrand 提交于 
      This is the very basic/initial version of virtio-mem. An introduction to
virtio-mem can be found in the Linux kernel driver [1]. While it can be
used in the current state for hotplug of a smaller amount of memory, it
will heavily benefit from resizeable memory regions in the future.

Each virtio-mem device manages a memory region (provided via a memory
backend). After requested by the hypervisor ("requested-size"), the
guest can try to plug/unplug blocks of memory within that region, in order
to reach the requested size. Initially, and after a reboot, all memory is
unplugged (except in special cases - reboot during postcopy).

The guest may only try to plug/unplug blocks of memory within the usable
region size. The usable region size is a little bigger than the
requested size, to give the device driver some flexibility. The usable
region size will only grow, except on reboots or when all memory is
requested to get unplugged. The guest can never plug more memory than
requested. Unplugged memory will get zapped/discarded, similar to in a
balloon device.

The block size is variable, however, it is always chosen in a way such that
THP splits are avoided (e.g., 2MB). The state of each block
(plugged/unplugged) is tracked in a bitmap.

As virtio-mem devices (e.g., virtio-mem-pci) will be memory devices, we now
expose "VirtioMEMDeviceInfo" via "query-memory-devices".

--------------------------------------------------------------------------

There are two important follow-up items that are in the works:
1. Resizeable memory regions: Use resizeable allocations/RAM blocks to
   grow/shrink along with the usable region size. This avoids creating
   initially very big VMAs, RAM blocks, and KVM slots.
2. Protection of unplugged memory: Make sure the gust cannot actually
   make use of unplugged memory.

Other follow-up items that are in the works:
1. Exclude unplugged memory during migration (via precopy notifier).
2. Handle remapping of memory.
3. Support for other architectures.

--------------------------------------------------------------------------

Example usage (virtio-mem-pci is introduced in follow-up patches):

Start QEMU with two virtio-mem devices (one per NUMA node):
 $ qemu-system-x86_64 -m 4G,maxmem=20G \
  -smp sockets=2,cores=2 \
  -numa node,nodeid=0,cpus=0-1 -numa node,nodeid=1,cpus=2-3 \
  [...]
  -object memory-backend-ram,id=mem0,size=8G \
  -device virtio-mem-pci,id=vm0,memdev=mem0,node=0,requested-size=0M \
  -object memory-backend-ram,id=mem1,size=8G \
  -device virtio-mem-pci,id=vm1,memdev=mem1,node=1,requested-size=1G

Query the configuration:
 (qemu) info memory-devices
 Memory device [virtio-mem]: "vm0"
   memaddr: 0x140000000
   node: 0
   requested-size: 0
   size: 0
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem0
 Memory device [virtio-mem]: "vm1"
   memaddr: 0x340000000
   node: 1
   requested-size: 1073741824
   size: 1073741824
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem1

Add some memory to node 0:
 (qemu) qom-set vm0 requested-size 500M

Remove some memory from node 1:
 (qemu) qom-set vm1 requested-size 200M

Query the configuration again:
 (qemu) info memory-devices
 Memory device [virtio-mem]: "vm0"
   memaddr: 0x140000000
   node: 0
   requested-size: 524288000
   size: 524288000
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem0
 Memory device [virtio-mem]: "vm1"
   memaddr: 0x340000000
   node: 1
   requested-size: 209715200
   size: 209715200
   max-size: 8589934592
   block-size: 2097152
   memdev: /objects/mem1

[1] https://lkml.kernel.org/r/20200311171422.10484-1-david@redhat.com

Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Eric Blake <eblake@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20200626072248.78761-11-david@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMichael S. Tsirkin <mst@redhat.com>
      910b2576
  3. 02 7月, 2020 5 次提交
  5. 30 6月, 2020 1 次提交
    • P
      hw/misc/pca9552: Add missing TypeInfo::class_size field · fc1bff95
      由 Philippe Mathieu-Daudé 提交于 
      When adding the generic PCA955xClass in commit 736132e4, we
forgot to set the class_size field. Fill it now to avoid:

  (gdb) run -machine mcimx6ul-evk -m 128M -display none -serial stdio -kernel ./OS.elf
  Starting program: ../../qemu/qemu/arm-softmmu/qemu-system-arm -machine mcimx6ul-evk -m 128M -display none -serial stdio -kernel ./OS.elf
  double free or corruption (!prev)
  Thread 1 "qemu-system-arm" received signal SIGABRT, Aborted.
  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
  (gdb) where
  #0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
  #1  0x00007ffff75d8859 in __GI_abort () at abort.c:79
  #2  0x00007ffff76433ee in __libc_message
      (action=action@entry=do_abort, fmt=fmt@entry=0x7ffff776d285 "%s\n")
      at ../sysdeps/posix/libc_fatal.c:155
  #3  0x00007ffff764b47c in malloc_printerr
      (str=str@entry=0x7ffff776f690 "double free or corruption (!prev)")
      at malloc.c:5347
  #4  0x00007ffff764d12c in _int_free
      (av=0x7ffff779eb80 <main_arena>, p=0x5555567a3990, have_lock=<optimized out>) at malloc.c:4317
  #5  0x0000555555c906c3 in type_initialize_interface
      (ti=ti@entry=0x5555565b8f40, interface_type=0x555556597ad0, parent_type=0x55555662ca10) at qom/object.c:259
  #6  0x0000555555c902da in type_initialize (ti=ti@entry=0x5555565b8f40)
      at qom/object.c:323
  #7  0x0000555555c90d20 in type_initialize (ti=0x5555565b8f40)
      at qom/object.c:1028

  $ valgrind --track-origins=yes qemu-system-arm -M mcimx6ul-evk -m 128M -display none -serial stdio -kernel ./OS.elf
  ==77479== Memcheck, a memory error detector
  ==77479== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
  ==77479== Using Valgrind-3.15.0 and LibVEX; rerun with -h for copyright info
  ==77479== Command: qemu-system-arm -M mcimx6ul-evk -m 128M -display none -serial stdio -kernel ./OS.elf
  ==77479==
  ==77479== Invalid write of size 2
  ==77479==    at 0x6D8322: pca9552_class_init (pca9552.c:424)
  ==77479==    by 0x844D1F: type_initialize (object.c:1029)
  ==77479==    by 0x844D1F: object_class_foreach_tramp (object.c:1016)
  ==77479==    by 0x4AE1057: g_hash_table_foreach (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.6400.2)
  ==77479==    by 0x8453A4: object_class_foreach (object.c:1038)
  ==77479==    by 0x8453A4: object_class_get_list (object.c:1095)
  ==77479==    by 0x556194: select_machine (vl.c:2416)
  ==77479==    by 0x556194: qemu_init (vl.c:3828)
  ==77479==    by 0x40AF9C: main (main.c:48)
  ==77479==  Address 0x583f108 is 0 bytes after a block of size 200 alloc'd
  ==77479==    at 0x483DD99: calloc (in /usr/lib/x86_64-linux-gnu/valgrind/vgpreload_memcheck-amd64-linux.so)
  ==77479==    by 0x4AF8D30: g_malloc0 (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.6400.2)
  ==77479==    by 0x844258: type_initialize.part.0 (object.c:306)
  ==77479==    by 0x844D1F: type_initialize (object.c:1029)
  ==77479==    by 0x844D1F: object_class_foreach_tramp (object.c:1016)
  ==77479==    by 0x4AE1057: g_hash_table_foreach (in /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0.6400.2)
  ==77479==    by 0x8453A4: object_class_foreach (object.c:1038)
  ==77479==    by 0x8453A4: object_class_get_list (object.c:1095)
  ==77479==    by 0x556194: select_machine (vl.c:2416)
  ==77479==    by 0x556194: qemu_init (vl.c:3828)
  ==77479==    by 0x40AF9C: main (main.c:48)

Fixes: 736132e4 ("hw/misc/pca9552: Add generic PCA955xClass")
Reported-by: NJean-Christophe DUBOIS <jcd@tribudubois.net>
Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: NJean-Christophe DUBOIS <jcd@tribudubois.net>
Message-id: 20200629074704.23028-1-f4bug@amsat.org
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
      fc1bff95
  7. 28 6月, 2020 1 次提交
  9. 26 6月, 2020 31 次提交